35 lines
No EOL
858 B
JavaScript
35 lines
No EOL
858 B
JavaScript
"use strict";
|
|
|
|
Object.defineProperty(exports, "__esModule", {
|
|
value: true
|
|
});
|
|
exports.deinterlace = void 0;
|
|
|
|
/**
|
|
* Deinterlace function from https://github.com/shachaf/jsgif
|
|
*/
|
|
var deinterlace = function deinterlace(pixels, width) {
|
|
var newPixels = new Array(pixels.length);
|
|
var rows = pixels.length / width;
|
|
|
|
var cpRow = function cpRow(toRow, fromRow) {
|
|
var fromPixels = pixels.slice(fromRow * width, (fromRow + 1) * width);
|
|
newPixels.splice.apply(newPixels, [toRow * width, width].concat(fromPixels));
|
|
}; // See appendix E.
|
|
|
|
|
|
var offsets = [0, 4, 2, 1];
|
|
var steps = [8, 8, 4, 2];
|
|
var fromRow = 0;
|
|
|
|
for (var pass = 0; pass < 4; pass++) {
|
|
for (var toRow = offsets[pass]; toRow < rows; toRow += steps[pass]) {
|
|
cpRow(toRow, fromRow);
|
|
fromRow++;
|
|
}
|
|
}
|
|
|
|
return newPixels;
|
|
};
|
|
|
|
exports.deinterlace = deinterlace; |